Power-wrench



H. F. MANN.

POWER WRENCH.

APPLICATION FILED MAR. 2a, 1918. RENEWED MAR. 22. I920.

Patented Oct. 12, 1920.,

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H. F. MANN.

POWER WRENCH. APPLICATION FILED MAR.- 23. 1918. RENEWED MAR. 22. 1920.

1,355Q239. Patented Oct. 12, 1920.

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[nurse STATES?" HORACE F. MANN, 0F ONAMIApMINNESOTA.

POWER-WRENCH.

Specification of Letters Patent.

Patented Oct. 12, 1920.

Application filed March 23, 1918, Serial No. 224,092. Renewed March 22, 1920. Serial No. 367,891.

. To aZZ whom it may concern:

of this kind which shall be effective in operation and at the same time have a minimum number of parts so that the device may be economically constructed and will not occupy any considerable floor space. An other object is to provide a power wrench which can be readily installed in any room having a ceiling and provided with a source of power.

The full objects and advantages of my invention will appear in connection with the detailed description thereof and are particularly pointed out in the claims.

In the drawings, illustrating the application of my invention in one form,

Figure 1 is a side view, partly in vertical section. Fig. 2 is a horizontal section on line 2-2 of Fig. 1. Fig. 3 is a horizontal section on line 33 of Fig. 1. Fig. 4 is a bottom plan view of the wrench jaws. Fig. 5 is a horizontal section on line 5-5 of Fig. 1. Fig. 6 is a top plan view, partly broken away, of the portion of the device shown in Fig. 5. Fig. 7 is a section on line 77 of Fig. 6. Fig. 8 is a side view of the wrench jaws. Fig. 9 is a view taken at right angles to Fig. 8 and partly in section.

As shown in the drawings, the device is suspended from the ceiling A by brackets 12 having half bearings at their lower ends, to which are secured half hearings on a casting 14. Rotatably mounted in these bearings and a bearing formed in a bracket 16 is a shaft 18 having a belt pulley 20 secured on its end. Secured to the shaft 18 just inside the two brackets 12 are two friction wheels 22 and 24. On the lower end of the casting 14 is a socket 26 in which is mounted an eccentric bearing 28 for a shaft 30. On the upper end of this shaft is secured a horizontal frictional wheel 32' which may be made to engage either of the wheels 22 or 24 by the means now to be described.

An arm 84 extends from the eccentric bearing 28 and to this arm are secured the ends of the two cords 36 and 38, which pass over rollers 40 and 42 and then extend downwardly and are secured to pedals 44 and 46 which are fastened to the floor B. Secured to the eccentric bearing 28 diametrically opposite the arm 34 is another arm 48 to which is secured the center of a coiled spr1ng50, the ends of which are attached to bolts 52 and 54 adjustably mounted in lugs 56 and 58 depending from the casting 14. The eccentric bearing 28 is turned in its socket 26 by depressing either of the pedals 44 or 46, as desired, and the frictional wheel 32 is thus brought into engagement with either of the friction wheels 22 or 24 according to the direction of rotation which it is desired to impart to the shaft 30. When neither of the pedals is depressed the wheel 32 is held in neutral position by the spring 50. Connected to the shaft 30 are a number of links 60 connected together in the manner of a chain, the lower link being connected to a shaft member 63, which has a round portion 62 and a square portion 64. The lower end of the portion 64 is adapted to receive a collar 66 having the depending flexible wrench jaws 68 and 7 0. The collar 66 is held in place by a spring pressed bolt I i 72 which enters a depression in the portion 64. The collar 66 may be made in two parts secured together by screws, as shown in Figs. 8 and 9. Slidably mounted on the jaws 68 and 70 is a conical sleeve 74 by means of which the jaws may be forced toward each other. On the lower end of the socket 26 is an annular flange 76, while on the shaft portion 62 is a bearing member 78. The flexible tube 80 is secured to the flange 76 and to the bearing 78 and completely incloses the links 60. On the shaft portion 64 is a sleeve 82 having a square opening to accommodate this shaft portion. The sleeve 82 is provided with a flange 84 and ball bearings 86 are placed between the two sides of this flange and two annular portions 88 and 90 have a handle member 92 which is hollow, as shown in Fig. 1. The sleeve 82 is rotatably mounted in the annular portions. To

the outer end of the handle member 92 is 7 100 on the ends of the member 94, these latter ends being bent toward each other and extending around the pivot 102, as best shown in Fig. 7. Pivoted to these ends at V scription thereof.

each side of the pivot 102 are a pair of links 104 and 106. The inner ends of these links are pivoted to a pair of dogs 108 and 1-10, both ofwhichare mounted on a pivot 112 which extends through the member 92. The periphery of the flange 84 is notched at 11dand when the member 9% is deflected, as

shown in Fig.5, the dog 110 will engage the bolts, since if the threads of the nut should not be properly engaged with those of the bolt and the nut be started by power the threads would be damaged before the machine could be stopped. v

The advantages and operation of my device will be obvious from the foregoing de The handle member 92 serves as a holding member to keep the jaws properly positioned with relation to the work, while the links 60 form a yielding connection between. the shaft 30 and the shaft 63. The flexible tube 80 constitutes a guard and prevents the operator cOinim in contact with the link connections. While the device may be used for. various purposes and the jaws may be used as a holder for different tools, the device is particularly adapted for use in tightening and unscrew ing nuts. I

I claim:

1. A power wrench comprising a rotatable shaft, jaws secured thereto, a power operated shaft, connections between said shafts including a pair of friction wheels secured to said power operated shaft, a friction wheel between said pair of wheels and the shaft to which said friction wheel is secured,

an eccentric bearing for said shaft, a spring connected to said bearing for holding said friction wheel out of engagement with said pair of wheels, a pair of flexible connections secured to said bearing for turning the same to bring said friction wheel into engagement with one or the other of the pair of friction wheels, and treadles to which said flexible connections are secured.

2. A wrench comprising a rotatable shaft,

jaws secured thereto, a hand operated support rotatably mounted upon SitlClShiLft, a

member pivoted to said support, a spring for signature.

HORACE MANN. 

